Cancer (abbr. Cnc, gen. Cancri)

The constellation of Cancer represents the Crab sent by Juno to save the Hydra in its battle with Hercules but
unfortunately crushed underfoot during the ensuing melee. It is a dim northern constellation (shaped a bit like Orion) and
the fourth sign of the zodiac, located between Castor and Pollux of Gemini and Regulus of Leo.

In former times the Sun used to lie in Cancer when it reached its
point farthest north – the time of the summer solstice – but
today, because of precession, the Sun passes through Cancer from late July
to early August.

X Cnc is a semi-regular variable with a striking red color
and an easy object with binoculars (magnitude range 5.6 to 7.5; period 195
days; R.A. 8h 55.4m, Dec. +17° 14'). Cancer also contains the open clusters Praesepe (M44) and M67 (NGC 2682). The
latter has at least 200 stars and is best seen through larger telescopes
(magnitude 6.9; diameter 30'; R.A. 08h 50.4m, Dec. +11° 49'. See below
for details of the constellation's brightest stars.